[01-git][check][Zig] Silenin Maxim

01-git/check-mssilenin/README.md

@@ -0,0 +1,21 @@
+# Сборка
+```
+zig build-exe check.zig
+```
+
+# Запуск
+```
+./check <dir> <start_hash>
+```
+
+# Пример вывода корректного дерева (dir ./correct)
+```
+checking commit hash; commit_hash=eac6b33b5eeae8d1e88a3343fc00e8e9c3a5ab120198aecd5c39665852dd0016
+checking commit hash; commit_hash=ebdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173
+checking commit hash; commit_hash=ea57e88f130debd48188990f1175c6cd891ef11017c1145fbf07f39ec2503aa8
+checking commit hash; commit_hash=86012759befd37636df5cc94ad673676a336616acd8b6156ae1bfdaf77465924
+All is correct!
+```
+
+# Некорректное дерево
+Может вернуться либо ошибка IncorrectHash, в случае неверного хеша в названии файла или директории, либо FileNotFound в случае несуществующего файла или директории

01-git/check-mssilenin/check.zig

@@ -0,0 +1,159 @@
+const std = @import("std");
+const sha2 = std.crypto.hash.sha2;
+const Allocator = std.mem.Allocator;
+
+const GB = 1 << 30;
+const HASH_SIZE = 32;
+const HEX_SIZE = 64;
+
+const ErrorIncorrectTree = error{
+    IncorrectHash,
+    FileNotFound,
+};
+
+fn checkBufHash(buf: []const u8, expected: []const u8) !void {
+    var hash: [HASH_SIZE]u8 = undefined;
+    sha2.Sha256.hash(buf, &hash, .{});
+
+    var slice_hash = std.mem.bytesAsSlice(u8, &hash);
+
+    var hex_bytes: [HEX_SIZE]u8 = undefined;
+    _ = try std.fmt.bufPrint(&hex_bytes, "{}", .{std.fmt.fmtSliceHexLower(slice_hash)});
+    var hex_slice = std.mem.bytesAsSlice(u8, &hex_bytes);
+
+    for (hex_slice, expected) |value1, value2| {
+        if (value1 != value2) {
+            return ErrorIncorrectTree.IncorrectHash;
+        }
+    }
+}
+
+fn readCommit(allocator: Allocator, name: []const u8) ![]const u8 {
+    var file = try std.fs.cwd().openFile(name, .{});
+    const file_buffer = try file.readToEndAlloc(allocator, GB);
+    file.close();
+
+    return file_buffer;
+}
+
+fn readAndCheckCommit(allocator: Allocator, hash: []const u8) ![]const u8 {
+    // read current commit
+    std.debug.print("checking commit hash; commit_hash={s}\n", .{hash});
+    var file_buffer = try readCommit(allocator, hash);
+
+    // check if hash of commit != name
+    try checkBufHash(file_buffer, hash);
+
+    return file_buffer;
+}
+
+fn findDir(allocator: Allocator, root_dir: []const u8, commit_hash: []const u8) ![]const u8 {
+    var current_commit_hash = try allocator.alloc(u8, commit_hash.len);
+    std.mem.copy(u8, current_commit_hash, commit_hash);
+
+    if (std.mem.eql(u8, root_dir, ".")) {
+        return current_commit_hash;
+    }
+
+    var dirs_it = std.mem.split(u8, root_dir, "/");
+
+    while (dirs_it.next()) |dir| {
+        var file_buffer = try readCommit(allocator, current_commit_hash);
+        defer allocator.free(file_buffer);
+
+        // split commit by '\n'
+        var lines = std.mem.split(u8, file_buffer, "\n");
+        while (lines.next()) |line| {
+            // skip empty line
+            if (line.len == 0) {
+                continue;
+            }
+
+            // split line by '/\t'
+            var it = std.mem.split(u8, line, "/\t");
+            var commit_dir = it.next();
+
+            // file -> skip
+            if (it.peek() == null) {
+                continue;
+            }
+
+            // find commit_dir == dir
+            if (std.mem.eql(u8, dir, commit_dir.?)) {
+                allocator.free(current_commit_hash);
+
+                var hash = it.peek().?;
+                current_commit_hash = try allocator.alloc(u8, hash.len);
+                std.mem.copy(u8, current_commit_hash, hash);
+                break;
+            }
+        }
+    }
+
+    if (std.mem.eql(u8, current_commit_hash, commit_hash)) {
+        std.debug.print("dir={s} is not found\n", .{root_dir});
+
+        return ErrorIncorrectTree.FileNotFound;
+    }
+
+    std.debug.print("found dir={s}\n", .{current_commit_hash});
+
+    return current_commit_hash;
+}
+
+fn checkFile(allocator: Allocator, name: []const u8) !void {
+    var file_buffer = try readAndCheckCommit(allocator, name);
+    defer allocator.free(file_buffer);
+}
+
+fn checkDir(allocator: Allocator, name: []const u8) !void {
+    var file_buffer = try readAndCheckCommit(allocator, name);
+    defer allocator.free(file_buffer);
+
+    // split commit by '\n'
+    var lines = std.mem.split(u8, file_buffer, "\n");
+    while (lines.next()) |line| {
+        // skip empty line
+        if (line.len == 0) {
+            continue;
+        }
+
+        // split line by '/\t'
+        var it = std.mem.split(u8, line, "/\t");
+        _ = it.next(); // skip name of dir
+
+        // file (len(it) == 1)
+        if (it.peek() == null) {
+            var file_it = std.mem.split(u8, line, ":\t");
+            _ = file_it.next(); // skip name of file
+
+            try checkFile(allocator, file_it.next().?);
+
+            continue;
+        }
+
+        // dir
+        try checkDir(allocator, it.next().?);
+    }
+}
+
+pub fn main() !void {
+    const allocator = std.heap.page_allocator;
+
+    var args = try std.process.argsAlloc(allocator);
+    defer std.process.argsFree(allocator, args);
+    if (args.len != 3) {
+        std.debug.print("Usage: ./check <dir> <start_hash>\n", .{});
+        return;
+    }
+
+    const dir = args[1];
+    const start_hash = args[2];
+
+    var hash = try findDir(allocator, dir, start_hash);
+    defer allocator.free(hash);
+
+    try checkDir(allocator, hash);
+
+    std.debug.print("All is correct!\n", .{});
+}

01-git/check-mssilenin/correct/61ec58ece347e6ac22f5227c642410bfad51e33bd2ca57e1f9d5b85502fa4ddf

@@ -0,0 +1,2 @@
+file.txt:	ebdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173
+subdir/	ea57e88f130debd48188990f1175c6cd891ef11017c1145fbf07f39ec2503aa8

01-git/check-mssilenin/correct/86012759befd37636df5cc94ad673676a336616acd8b6156ae1bfdaf77465924

@@ -0,0 +1 @@
+smth

01-git/check-mssilenin/correct/ea57e88f130debd48188990f1175c6cd891ef11017c1145fbf07f39ec2503aa8

@@ -0,0 +1 @@
+subdir_file.txt:	86012759befd37636df5cc94ad673676a336616acd8b6156ae1bfdaf77465924

01-git/check-mssilenin/correct/eac6b33b5eeae8d1e88a3343fc00e8e9c3a5ab120198aecd5c39665852dd0016

@@ -0,0 +1,2 @@
+file.txt:	ebdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173
+subdir/	ea57e88f130debd48188990f1175c6cd891ef11017c1145fbf07f39ec2503aa8

01-git/check-mssilenin/correct/ebdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173

@@ -0,0 +1 @@
+so so

01-git/check-mssilenin/incorrect_dir_hash/61ec58ece347e6ac22f5227c642410bfad51e33bd2ca57e1f9d5b85502fa4ddf

@@ -0,0 +1 @@
+file.txt:	ebdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173

01-git/check-mssilenin/incorrect_dir_hash/ebdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173

@@ -0,0 +1 @@
+so so

01-git/check-mssilenin/incorrect_file_hash/dbdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173

@@ -0,0 +1 @@
+so so

01-git/check-mssilenin/incorrect_file_hash/e67e94fb8713fe93b620dd2f2054fcc11d70d820fedd6a3125247fb93dee8f3f

@@ -0,0 +1 @@
+file.txt:	dbdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173

01-git/check-mssilenin/unknown_file/61ec58ece347e6ac22f5227c642410bfad51e33bd2ca57e1f9d5b85502fa4ddf

@@ -0,0 +1,2 @@
+file.txt:	ebdd7b80aa4838dc4585af7f7d47b643024be479822f6c59b7c6313ce8322173
+subdir/	ea57e88f130debd48188990f1175c6cd891ef11017c1145fbf07f39ec2503aa8